Masticatory biomechanics in the rabbit: a multi-body dynamics analysis

Abstract

Multi-body dynamics is a powerful engineering tool which is becoming increasingly popular for the simulation and analysis of skull biomechanics. This paper presents the first application of multi-body dynamics to analyse the biomechanics of the rabbit skull. A model has been constructed through the combination of manual dissection and three-dimensional imaging techniques (magnetic resonance imaging and micro-computed tomography). Individual muscles are represented with multiple layers, thus more accurately modelling muscle fibres with complex lines of action. Model validity was sought through comparing experimentally measured maximum incisor bite forces with those predicted by the model. Simulations of molar biting highlighted the ability of the masticatory system to alter recruitment of two muscle groups, in order to generate shearing or crushing movements. Molar shearing is capable of processing a food bolus in all three orthogonal directions, whereas molar crushing and incisor biting are predominately directed vertically. Simulations also show that the masticatory system is adapted to process foods through several cycles with low muscle activations, presumably in order to prevent rapidly fatiguing fast fibres during repeated chewing cycles. Our study demonstrates the usefulness of a validated multi-body dynamics model for investigating feeding biomechanics in the rabbit, and shows the potential for complementing and eventually reducing in vivo experiments.

The Early Evolution of Biting–Chewing Performance in Hexapoda

“…An emerging technique to study aspects of the biomechanics, such as the kinematics and kinetics, of an arbitrarily sized organism is musculoskeletal modeling of the particular movement system (Curtis et al 2008;Shi et al 2012;Watson et al 2014). Such simulations are subsumed under the umbrella term multibody dynamics analysis (MDA), placing an emphasis on the investigation of moving structures which are connected to each other by joints and/or muscles.…”

Non‐Destructive Determination of Muscle Architectural Variables Through the Use of DiceCT

“…As mechanical advantage will vary throughout a single muscle, regional differences in architectural parameters such as fascicle length or pennation angle may be related to differences in moment arm length between anteriorly-and posteriorly-positioned fascicles within this muscle. Integrating data on muscle fascicle length and orientation into digital mediums of biomechanical modeling such as multibody dynamics (Curtis et al, 2008;Shi et al, 2012;Fitton et al, 2012;Gr€ oning et al, 2013;Watson et al, 2014) or finite element analysis (Kupczik et al, 2007(Kupczik et al, , 2009Chalk et al, 2011;Wang et al, 2010;Dumont et al, 2011;Ross et al, 2011;Tseng et al, 2011;Fitton et al, 2012;Smith et al, 2015) may allow us to directly address the relationship between muscle architectural variables and other functional determinants of muscle performance.…”

Muscle moment arm analyses applied to vertebrate paleontology: a case study usingStegosaurus stenopsMarsh, 1887

“…The corollary of grouping muscles by function, therefore, is that it may be necessary to model a single muscle as two separate functional units, particularly when osteological evidence suggests the presence of two When subdividing fan-shaped muscles, the criteria for selecting the number and location of multiple lines of action are not always made clear, and may be related to position ('superficial' vs. 'deep'), perceived function, or selected in order to capture differing fiber directions within the muscle. The practice of partitioning muscles with large attachment sites is common in human biomechanical modelling (Delp et al, 1990;van der Helm and Veenbaas, 1991;Holzbaur et al, 2005;Chadwick et al, 2009;Arnold et al, 2010;Webb et al, 2012) and is increasingly applied to other extant taxa, particularly in MBDA of skull function (Wroe et al, 2007(Wroe et al, , 2013Gröning et al, 2013;Watson et al, 2014). Modern studies benefit from the incorporation of dissection data and MRI-based imaging of in-situ 3D muscle geometry when subdividing muscles for this purpose.…”